Apparatus for feeding lime to blast-furnaces.



I. MORGAN. APPARATUS FOR FEEDING LIME TO BLAST FURNACES.

' v APPLICATION FILED NOV. 3, I9I3- LS'P@ SHI I. G MQRGN. APPARATUS FORFEEDING LIME T0 BLAST FURNACES.

APPLICATION FILED INV. 3. ISIS.

Fatented Apts. 2?', 9l5.

2 sains-SMU 2.

from thl.` steile lcavin' calcium oXid or a zo 5137 ,dir

limi-lm@ @lli/illus.

i JAMES G. MORGAN, F JACKSN, 01H10.

APPARATUS FOR FEEDXNG LME TO BLAST-FURNACES.

'following is a specilication.

My invention relates to blast furnaces.,

`and.particularly to means whereby lime may beufed into the shalt of thefurnace and properly distributed therein. The use of lime in the form ofcalcium oxitl (CaO)A in a blast furnace for luxing purposes has for manyyears been recognized as theoretically having a great advantage over theuse of limestone, calcium carbonate {CaCQ3). g'lllliistheory is based onthe fact that in calcium oXid which is made from limestone, 'the carbondioxid (CU2) is driven oil outside of the furnace. lVhen limestone inthe form of calcium carbonate is charge in at the top olf the furnace,it begins to decompose at about 11000 Fahr., and gives oli 'carbondioxid. The decomposition is complete at about 16000 Fahr. andpractically all of the carbon dioxid'hasbcen driven olli lime. Thecarbon dioxid gas passing up- Ward through the stock, comes in contact.with the coke ci' the charge and extracts an amount of carbon from thecoke equal to that contained in thccarbon dioxid gas and Vforms carbonmonoxid (CO). ln pure limestone this loss of coke amounts to about 14llos.l of coketo every 100 lbs. oi limestone used, but for the limestonegenerally used in most furnaces, the loss ol' coke will amount to aboutl2 lbs. to every l0() lbs. of limestone used. The (,:lmuling` of lime in.the form of calcium oxid into the top et' the furnace would seem toovercome this loss of carbon, inasmuch as the carbon dioxid has beendriven oft' outside of the furnace before it is introduced, but asthccalcium oXid sinks down in the furnacevvith the stock it comes incontact with the carbon dioxid gas formed by the reduction of the oresby the carbon inonoxid gas, and .comes in contact with this carbondioxid at temperatures atvvhich the calcium oxid has a strong affinityfor the carbon dioxid. rlFhe following reaction therefore takes place:CaO-l-COgzCaCOX, that is, the lime is again turned into limestone(calcium carbonate) by the addition of the carbon di- Specicaton or'Letters Patent.

scripcion of one chute with its valve ar- Patented Apr. 2"?, fr.'

Application liletl November 3. 193. Serial Elo. 799,6136.

oxid which is later released. aga-in 4farther down in the furnace andascending through the stock comes in contact with the colte, therebycansino' a loss by absorption el carbon in the manner heretoforeexplained.

The primary object or' my invention,4

therefore, is to ohvlate othis loss of carbon and to accelerate' otherreactions and conditions condueiveto good furnace practice, byintroducing lime into the furnace at point Where practically no carbondioxid gas eX f ists.

A further object of the' invention is to provide means for introducinglime into a furnace stack so formed that the gas in the :furnace willnot escape While thelime is being introduced.

A further object of the invention is tc so construct this means i'orintroducing lime that a suliicient clearance for the steelt as it rollsell' the 'furnace bell will be provided.

Other objects will appear in the course of the following description.

My invention is illustrated in the accompanying drawings wherein:

Figure l is a. vertical diametrical section n of a. blast furnaceconstructed in accordance with my invention. Fig. 2 is a section on theline 2 2 of Fig. l. Fig. 3 is a lengitudinal vertical section of one ofthe lime chutes with its valves, mentary perspective view of one of thelime chutes illustrating the arrangement of vvater inlet and outletpipes. Corresponding and like parts are referred to in the followingdescription and indicated in all the views of the accompanying drawingsby the same reference characters.

Referring to these drawings, 2 designates the shaft of a blast furnaceof any ordinary construction. My invention is not limited to anyparticular form of blast furnace and therefore l wish it understood thatthe illustration of the blast furnace used' by me is very largelydiagrannnatic. The interior diameter of the shaft gradually enlargesdownward a certain portion of its length to the bosli 3 and 'then iscontracted as at 4 and opens into the lwell 5 into which open the twyersG. A'

Extending downward from the mouth of the furnace to anydesired orsuitable extentare a plurality of chutes, each chute being designatedgenerally 7. All of the chutes have the same form and hence aderangement will apply to all of the chutes. As illustrated in Figl 3,each chute is prefer ably formed of three sections of pipe or tubingdesignated 8, 9 and 10. Each section 1s preferably inwardly flanged atone or bothy endsv so that the sections may be joined to each other bymeans of bolts or rivets 1l. Each section may be water jacketed, Athewall being double to provide the water space 12. Preferably the waterspace of each jacket is divided into a pluralityy of compartments 12a,12b, 120, each compartment having an induction pipe 13 and an outletpipe 14 to provide for the circulation of cold water. Each compartmentis formed with a vertical partition extending nearly to the bottom ofthe compartment, the inlet for that compartment being on one side of.the partition while the outlet pipe is on the opposite side. The wateris admitted by the pipe at the top of the compartment-then it passesdown the compartment and crosses over to the bottom of the compartmenton one' side of the partition and passes up and :is discharged at thetop thus securing a circulation of water within each compartment. fcou-rse, l do not wish to be limited to the precise construction of thisjacket 12 or its subdivision into water spaces.V

' l f The section 8 of the chutevis formed with ai valve seat 15 on itsinner face, 'this valve seat being downwardly and vcentrally extended toprovide a central opening 16. The section 9 is also provided with a likevalve seat 17. @ducting with the valve seat l5 is the invertedbell-shaped valve 18 which lits the central opening 16, and coactingwith the valve seat 17 is the inverted belln'shaped valve 19. The valve18 is attached to a tubular rod 2O while the valve 19 is attached'to arod 21 which. extends upward through the tubular rod. Thus the valves 18and 19 have independent movement.

rllhe center of the shaft 2 is provided with usual hopper 22 controlledby the usual inverted cone-shaped valve or bell 23. This valve or bell`23 is intendedto be operated by means of any usual mechanism forthispurpose, this mechanism being indicated in -Fig 1 by the referencenumeral 2li. lt is -to be understood, of course, that a suitableoperating rig is also to be used for opening oir-closinfy the valves 18and 19, said rig to be placed3 at a convenient point at the top of theshaft and to be operated by steam, compressed airfor any other of theusual' instrumentalities. The rig for operating these valve rods'21 and22 will be of very much the same form as the mechanism used foroperating double bells on blast furnaces. Such a rig is illustrated inFigs, 1 and 3, Each. valve is controlled by its own. rig; which includesa walking beam 25 to which one end of the valve rod is connected. Apiston rod 26 is connected to the other end ofthe walking beam and leadsto a glston operating in a steam cylinder 2'?.

lteam is supplied to this cylinder through either the pipe 28 or 29according to the desired direction of movement of the piston. It is'obvious that as each furnace has conditions peculiar to itself, theoperating mechanism for actuating the valves will be arranged to suitthe particular necessity of each furnace. lt is to be noted that thechutes Z 'are disposed partly in the wall of the shaft?, as illustratedin Fig. 2 so as I to admit of sufficient clearance for stock as it rollsoff the furnace bell.

The bells or valves in the chutes are to be operated as follows: Lime isdischarged into the iirst division the valve or bell 18 by which it isretained 1s lowered allowing the lime to pass into the second divisionor chamber whose valvefl at this time is closed.

or chamber 8. Then The valve 18 is then raised to close the opening i6and the valve 19 is lowered, allowing the lime to pass on -into thefurnace. The upper bell or valve 18 remains closed during this operationin order to prevent the escape of gases.

It will be noted that thechutes extendv down far enough into the shaftto discharge lime into the furnace at a point where practically nocarbon dioxid gas exists.` The advantages of the invention are asfollows First, it will eiiiect a saving in fuel of from twelve tofourteen pounds of coke to every hundred pounds of limestone used.Second, by use of my invention, lime may be used, and by using limeinstead of limestone an additional savingof fuel is secured, due :o adecreased volume of gas escaping from the furnace as this gas hasalready been driven olf the-limestone outside of the furnace'in theprocess of converting, the limestone into lime. Third, an additionalsaving in fuel will be secured due to a decreased volume of gas escapingfrom the furnace top f as a result of a decreased requirement for air.Fourth, a further lfuel saving will be secured, due to a decreased rateof travel of the gases passing through the stock. Fifth, inasmuch as theupper portion of the stock will be in cooler condition, an additionalsaving of fuel will be secured. Sixth, my invention will increase theoutput of iron because of the larger proportion of iron bearing materialin each charge. rllhis is due to the fact that 'when a fixed amount oflimestone CaCO3, is reduced to lime, CaO, it

occupies less space, and as this space is of necessity. taken up byother materials, largely iron bearing materials, it follows that outputof iron will necessarily be increased. Seventh, it will effect anadditional increase and output of iron and a saving in fuel due toconditions secured by the use of my in from the upper end of thefurnace, being loy vention, both lchemical and physical, which producegood smelting conditions."

It will be apparent that lthe machinery and equipment will not besubjected to as great an amount of worli per ton of iron when liineisused, instead -of limestone, and the lime is dischar ed into the furnaceat the oint indicate This will insure a steadier, run, less breakage,and thereby cause an increase in the output of iron and likewise asaving in fuel which such steady operation always produces.

While I have illustrated what I believe to be a thoroughly effectiveform vof my apparatus, I wish it understood that I need 'not be limitedto this as the specific construction of the chutes, the manner ofoperating the bells, etc., may be varied to suit any desired condition.

What I claim is:

1. In a blast furnace, a chute of straight line extent projectingvertically downward cated wholly therein and being open at its lowerend, the lower end being on a level above the zone'of fusion and belowthe zone where carbon dioxid gas exists.

2. In a blast furnace whose walls incline downward and outward to thebosh and then downward and centrally, a chute extending straightdownward from the upper end of whose walls extends downward and outwardtb the bosh., a chute, located interiorly of the furnace extendingstraight downward from the upper end of the furnace and disposed at itsupper end partially in the furnace wall and. with its lower end whollywithin the furnace and clear of the wall.

5. In a blast furnace, a chute located wihin the furnace extendingdownward from the upper end of the furnace and disposed against theinner face of the wall thereof,

the chute terminating short of the bosh and f being adapted to dischargematter out of Contact with the wall,

6. In a blast furnace, a chute located within the furnace extendingstraight downward from the mouth of the furnace and disposed against theinner face of the wall thereof, the lower end of the chute being open,and a plurality of valves in each chute controlling the passage ofmaterial through the chute and the upward passage of gases through thechute.

7. The combination with a blast furnace, i

of a chute for introducing lime or other inaterial into the furnace,said chute Vextending straight downward from the top of the furnace andbeing disposed against the inner face of the wall thereof, said chutebeing formed in a` plurality of sections, and independently operatedvalves spaced from each other and controllingthe passage of materialthrough said chute.

8. In a blast furnace, a plurality of chutes for introducing linie orother material into the furnace, said chutes being disposed against theinner face of the wall of the furnace and extending straight downwardand discharging at their lower ends above the bush.v

In testimony whereof I aix my signature in presence of two witnesses.

JAMES G. MORGAN. [n 5.] Witnesses: i

GEO. J. Jonas, JOHN A. Rossnn.

